c++ - 如何确保将对象分配给变量

Question

我有一门课来测量和记录范围内的时间消耗

class MeasureTime {
  public:
    MeasureTime(const std::string log_message) : log_message(log_message), t_start(std::chrono::steady_clock::now()){};
    ~MeasureTime() {
        const auto t_end = std::chrono::steady_clock::now();
        const auto duration = std::chrono::duration_cast<std::chrono::duration<double>>(t_end - t_start).count();
        std::cout << "Time measurement: " << log_message << " took " << duration " seconds.\n";
    }

  private:
    const std::chrono::_V2::steady_clock::time_point t_start;
    const std::string log_message;
};

如果我有这样的范围，一切正常。

{
    MeasureTime measureTime("message");
    // do something
} // The destructor of MeasureTime is called here

另一方面，如果我只是构造对象而不将其分配给变量，则立即调用构造函数并且时间测量失败。

{
    MeasureTime("message"); // The destructor of MeasureTime is called immediately here
    // do something
}

如何确保将创建的对象分配给对象？

标签： c++variable-assignmentdestructor